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      DScaler -- Gradual Noise filter
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          <FONT FACE="Verdana, Arial, Helvetica, sans-serif" SIZE="5"><B>
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           Gradual Noise Filter <!-- #EndEditable --></B></FONT> 
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          <P>
            This filter cleans up the picture, averaging out visual noise between frames.
          </P>
          <P>
            When colors change just a little, the filter decides that it&rsquo;s probably noise, and
            only slightly changes the color from the previous frame. As the change in color
            increases, the filter becomes more and more convinced that the change is due to motion
            rather than noise&nbsp;&mdash; and the new color gets more and more weight.
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            <B><FONT FACE="Arial" SIZE="4">
              The Settings
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            <B><FONT FACE="Arial" COLOR="#993300">
              Noise Reduction
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          <P>
            The higher you set it, the more you&rsquo;ll cut down on noise&nbsp;&mdash; but the more
            blurring you will see. In general, reasonable settings range from 10 (to soften
            the occasional speckle without artifacts) to 20 (to reduce noise with minimal
            artifacts) to 40 (for better reduction, but visible blurring) up to 70 (to average out
            really heavy noise at the cost of bad blurring). At extremely high <FONT COLOR=
            "#993300">Noise Reduction</FONT> values, you&rsquo;ll start to see artifactual
            vertical lines.
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          <P>
            To choose a setting for it, turn on just about any comedy or drama&nbsp;&mdash; anything
            with close-ups of moving faces. Increase <FONT COLOR="#993300">Noise Reduction</FONT> until
            the suppression of noise doesn&rsquo;t seem worth the blur.
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          <P>
            <B><FONT FACE="Arial" COLOR="#993300">
              Fast Memory Access
            </FONT></B>
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          <P>
            This is a <A HREF="Fast Memory Access.htm">compatibility
            setting</A> which should normally be turned on.
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            <B><FONT FACE="Arial" SIZE="4">
              Noise Notes
            </FONT></B>
          </P>
          <P>
            You might want to take a look at <A HREF=
            "AdaptiveNoise.htm#Fun With Noise">Fun With Noise</A>, a discussion of noise filtering
            in general.
          </P>
          <P>
            Don&rsquo;t run this filter at the same time as the
            <A HREF="Noise.htm">Temporal Noise</A> filter. Together they give you the &ldquo;comical
            posterization and speckling&rdquo; filter.
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            <B><FONT FACE="Arial" SIZE="4">
              Filter changes
            </FONT></B>
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					<P>
					DScaler version 4.1 &mdash; Slightly changed the amount of blending to
					more closely approximate the calculated ideal.  As a side effect, you
					may want to drop your <FONT COLOR="#993300">Noise Reduction</FONT> setting
					by a few ponits.
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